It is known from the prior art to arrange electronic components, such as converters or filters, in particular of devices for generating electrical energy, in power switch cabinets. Wind turbines are often equipped with doubly-fed asynchronous machines, since in this way only partial outputs have to be transported via the converters of the equipment. However, with rotational speeds below the synchronous rotational speed of the generator the efficiency of the equipment drops. Accordingly, synchronous machines with full power converters are increasingly used. In these systems, however, the overall power to be supplied to the mains is fed through a converter, so that these have to be suitably dimensioned and constructed so that they are scaleable. Furthermore, due to the required relatively larger outputs additional demands are for example placed on cooling, combined at the same time with a compact construction of the switch cabinets.
The printed specification EP1903848B1 describes a modular frequency converter, in which the power electronics part is provided with wheels, as well as an installation cabinet for accommodating the power electronics part. Complicated and costly plug-and-socket connections are necessary to connect the power electronics part to the remainder of the frequency converter.
The printed specification U.S. Pat. No. 7,545,052 B2 describes a method that is intended to improve the efficiency and the reliability of converter modules in a current generation device in a wind turbine. For this purpose the wind turbine comprises a plurality of converter modules, which are connected in parallel on both the generator side and the mains side, and in which the converter modules can be independently switched on and off depending on a parameter. In order to prevent overheating, the converter modules should for example be operated alternately or switched on and off corresponding to the power produced by the generator. During the switching on and off procedure the converter modules pass through several specific switching states, which are regulated from a central CPU. This requires a complicated cabling between the central CPU and the converter modules. Furthermore, in the event of a defect the complete module has to be replaced.
The printed specification U.S. Pat. No. 7,859,838 B2 relates to an arrangement for accommodating a converter or frequency changer in a switch cabinet. The frame of the switch cabinet should in this connection be of modular construction, so that the components of the frequency converter can be installed in the switch cabinet frame modules before the switch cabinet is brought to the installation site. The disadvantage in this case however is that the individual components of the frequency converter are distributed in various cabinets, which furthermore requires complicated cabling. After the installation in the factory a subsequent scalability in situ is possible only with considerable effort and expenditure. In addition the individual frame modules require a relatively large amount of space.